EP 0537034 A1 19930414 - Method of manufacturing a washer.
Title (en)
Method of manufacturing a washer.
Title (de)
Verfahren zum Herstellen einer Unterlegscheibe.
Title (fr)
Procédé de fabrication d'une rondelle.
Publication
Application
Priority
US 77241591 A 19911007
Abstract (en)
A method of manufacturing a washer includes the steps of: (a) feeding a metal wire (1) into a die (2) having a bearing face (2') and a through hole (2=) which opens to the bearing face (2') so as to permit the metal wire (1) in the through hole (2=) to protrude out of the bearing face (2') at a predetermined length; (b) punching the protruded metal wire (1') against the bearing face (2') to form a disc (1=) with a punching head (3') which includes a core (4) and a shell (3); (c) punching the disc (1=) to form a central hole on the disc (1=) by forcing the core (4) out of the shell (3) and into the through hole (2=); and (d) retracting the punching head (3') to allow the disc (1=) to separate from the metal wire (1). <IMAGE> <IMAGE>
IPC 1-7
IPC 8 full level
B21F 37/04 (2006.01); B21K 1/76 (2006.01)
CPC (source: EP US)
B21F 37/04 (2013.01 - EP US); B21K 1/761 (2013.01 - EP US)
Citation (search report)
- [X] US 1483156 A 19240212 - GRAHAM BROWNE GOUVERNEUR
- [X] US 1355434 A 19201012 - SULTEMEYER CHARLES F
- [X] US 4435973 A 19840313 - NAKAZAWA SHIGEO [JP], et al
- [A] US 1452535 A 19230424 - SULTEMEYER CHARLES F
- [A] FR 661584 A 19290726
- [A] DE 94892 C
- [A] FR 715656 A 19311207 - RINGFEDER GMBH
- [X] PATENT ABSTRACTS OF JAPAN vol. 8, no. 154 (M-310)(1591) 18 July 1984 & JP-A-59 50 945 ( TANAKA KIKINZOKU KOGYO )
Designated contracting state (EPC)
AT BE CH DE DK ES FR GB GR IT LI LU NL PT SE
DOCDB simple family (publication)
EP 0537034 A1 19930414; AU 2075592 A 19930408; AU 653242 B2 19940922; BR 9202881 A 19930427; CA 2074922 A1 19930408; CA 2074922 C 19960305; CN 1025011 C 19940615; CN 1071610 A 19930505; MX 9204475 A 19930401; US 5259819 A 19931109
DOCDB simple family (application)
EP 92402182 A 19920729; AU 2075592 A 19920731; BR 9202881 A 19920727; CA 2074922 A 19920729; CN 92108773 A 19920727; MX 9204475 A 19920731; US 77241591 A 19911007